Sep

30

Charles “Chuck” W. Hull, the inventor of stereolithography and founder of 3D Systems

A huge and diverse industry has grown out of the development of stereolithography, an additive manufacturing technology also known as optical fabrication or photo solidification, that has been used in 3D printing in the last three decades, not the least of which is regenerative medicine. Chuck Hull, executive vice president, and CTO of 3D Systems, along with Doug Neckers, CEO of Spectra Group Limited, are pioneers of Hull’s patented technology that spawned an age of 3D printing. Today, prototypes of airplane wings, musical instruments, auto parts, and medical prostheses can be created on demand in a matter of hours, and printers capable of producing intricate 3D objects can be had for the price of a high-end TV.

Development of SLA and 3D Systems

SLA is a process of building 3D structures from a computerized design. Multiple thin layers of a liquid UV-curable photopolymer resin are cured, one on top of another, using a UV laser to trace and solidify a pattern and causing each layer to adhere to the layer below. SLA greatly reduced the time it takes for designers and engineers to create a concept design or functional 3D prototype. After patenting the 3D manufacturing process in 1986, Hull founded 3D Systems, which commercialized the first rapid-prototyping system for computer-aided-design software. The company is now a leading provider of commercial and household 3D printers and design-productivity tools for digital manufacturing.

3D Systems’ most recent innovation is a $1,300 Cube printer that makes plastic 3D objects such as toys and jewelry and is marketed to consumers, hobby designers, and garage entrepreneurs. Hull calls this latest advancement a “democratization” of access to 3D printing. 3D Systems has been extremely successful, reporting revenues of $90.5 million in the third quarter of 2012, a 57% increase over the same period in 2011. It announced in October 2012 that it expects about $350 million in revenues by the end of 2012.

Hull has a BS in engineering physics from University of Colorado (USA) and an honorary doctorate in engineering from Loughborough University (UK). He was working to develop UV-curable resins for Ultra Violet Products in California when he made the breakthrough.

In the early 1980s, Dr. Hull wondered if photopolymer chemistry could be imaged to quickly make first-article (prototype) plastic parts, since it took six to eight weeks to get first-article parts from the traditional tool-making and molding processes. And then the design usually had problems, and it had to be done over. Designing in plastic was a very time-consuming and expensive process. At that time, stereolithography created great interest because it solved the first-article problem; it was a rapid prototyping system. Based on that, the company grew rapidly, expanded the range of stereolithography systems, and also developed lower-cost ink-jet-based 3D printers. Since then, quite a few competing companies and technologies emerged, each with their own approach to 3D printing. However, over the years, 3D Systems continued to develop new types of printers, and the company acquired several other companies and technologies in the field.

The technology required mastering photochemistry, laser optics, optical scanning, precision mechanical mechanisms, machine-control software, 3D image manipulation software, process engineering, and system integration. Hull created the first stereolithography system by himself in a lab that his employer let me use. This was very basic, but it demonstrated the concept. Based on that, he formed the new company, 3D Systems, and brought in all the special talent to develop commercial systems. There was tremendous interest from the beginning, and the company’s initial customers invested alongside with the company to learn and help evolve the technology to where it is today.

Fortunately, the time was right to deliver an affordable 3D printer. That and working on great 3D content for anyone and everyone to take advantage of, were the main challenges in offering a compelling consumer introduction to 3D printing. According to Hull, production systems using SLA and selective laser sintering (SLS) still demand a premium in the market because their capabilities to suit customers’ requirements is evolving. The real price breakthrough has been in entry-level systems – delivering great value for the cost – and in the ability to deliver increasing levels of functionality from years of experience at the high end to the professional 3D-printer market.

The company is on a mission to place creative tools into the hands of everyone – without regard for their technical abilities. Hull sees a future when everyone can create and make in 3D with true coloring-book simplicity. In the past 25 years, a few hundred thousand people have been able to design with complete freedom of creation. Just imagine what happens when billions of us gain access? The level of innovation and creativity should far surpass anything we know today.

Hull’s favorite is the very first cup that was printed. His wife keeps it with her still today. He also stated that while there are many amazing things have been printed, perhaps the medical model that surgeons used in 2003 to successfully separate the Egyptian twins joined at the head will always remain one of his most important objects.

The U.K. and U.S. governments are among many nations funding programs to accelerate the development and commercialization of laser-based additive manufacturing technologies. The U.K. Technology Strategy Board will invest millions of pounds on 3D printing technologies with its “Inspiring New Design Freedoms in Additive Manufacturing” competition. The United States in 2012 launched a pilot institute to serve as a proof-of-concept for its National Network of Manufacturing Innovation. The pilot institute is located in Ohio and will be focused on additive manufacturing technologies such as 3D printing. Lawrence Livermore National Laboratory (USA) is planning a major push in its research programs devoted to additive manufacturing technologies like stereolithography. In addition, at its Center for Micro and Nano Technology in California (USA), LLNL develops applications for the Departments of Energy, Defense, and Homeland Security. The lab will collaborate with U.S. manufacturers to develop efficient technologies for their manufacturing processes.

Below is an example of LLNL’s printed 3D structures.

Sources: SPIE: (SPIE is the international society for optics and photonics);Forbes (2013); Business Week (2013); Wikipedia